Upgraded from 16.04 to 18.04 and now my pc can't boot ! Help!

[muradean]

Intro: Hi guys, today I've messed up big time. I was programming on R and I needed a package, and I tried to install it, but it had some dependencies problems I couldnt solve, so i figure out, "hey!?!?! What if i upgrade to ubuntu 18.04 Maybe then I'll be able to play around with some random forests in rStudio."

Fast forward, i upgraded, then when i clicked to boot, the ubuntu screen with the 4 dots appeared, then :

1-The screen lost power for 1 second.
2-The screen came back in black for 5 seconds.
3-Some texted flashed up with a bunch of oks, but with a failed that said : [FAILED] failed to start AppArmor initialization

And these 3 steps go on in an infinite cycle.

Now, when i turn on my pc i can go on in Grub, which i have no experience so far. And when i go on advanced options for ubuntu i can see:

Ubuntu, with Linux 4.15.0-30-generic
Ubuntu, with Linux 4.15.0-30-generic (upstart)
Ubuntu, with Linux 4.15.0-30-generic (recovery mode)

Ubuntu, with Linux 4.15.0-29-generic
Ubuntu, with Linux 4.15.0-29-generic (upstart)
Ubuntu, with Linux 4.15.0-29-generic (recovery mode)

Ubuntu, with Linux 4.15.0-20-generic
Ubuntu, with Linux 4.15.0-20-generic (upstart)
Ubuntu, with Linux 4.15.0-20-generic (recovery mode)

So i would ask you dearly if anybody can help me.

I have 2 goals:
First - To solve this problem and start using and enjoying ubuntu 18 normally for a very long time.
Second(if first is impossible) - If not possible to solve this, and i need to boot the OS from a hard-drive is there anyway i can get the files from my Desktop folder and pass them to a hard drive ( i had a lot of college work there) ...

Thanks a lot for the attention.

[mörgæs]

Hi, welcome to the fora.

Are you able to boot into recovery mode?

[muradean]

If you are refering to that menu with a pink background, yes i am.

[mörgæs]

Good, then you have a method for saving your files to an external drive.

I normally don't want to struggle with a system which has been wrecked by an upgrade. I would go for a fresh install of 18.04.1 and keep it updated (not upgraded) through 2023.